larese@bnlux0.bnl.gov (john z larese) (07/13/88)
I have just changed my place of work and I am now working in a High security nuclear reactor. As employees, such as myself enter the building, we pass all bags through a X-Ray detector and walk through a metal detector. My question is, do any magnetic fields exist in either equipment that might be high enough to damage Mag tapes? Sorry if this isn't the right newsgroup, but this seemed to be a general question. John Larese
eric@hector.UUCP (Eric Lavitsky) (07/16/88)
In article <588@bnlux0.bnl.gov> larese@bnlux0.UUCP (john z larese) writes: >My question is, do any magnetic fields exist in either equipment >that might be high enough to damage Mag tapes? > >Sorry if this isn't the right newsgroup, but this seemed to be >a general question. > >John Larese I have had a videotape destroyed by a metal detector, but never by an X-Ray machine. I believe that in reality, metal detectors throw off strong magnetic fields that will erase magnetic media while X-Rays will ony harm photographic material. X-Ray machines haven't damaged floppies on me yet... Eric ARPA: eric@topaz.rutgers.edu or eric@ulysses.att.com UUCP: {wherever!}ulysses!eric or {wherever!}rutgers!topaz!eric SNAIL: 34 Maplehurst Ln, Piscataway, NJ 08854 "To err is human; To really f*ck up requires the root password."
dlm@cuuxb.ATT.COM (Dennis L. Mumaugh) (07/16/88)
In article <588@bnlux0.bnl.gov> larese@bnlux0.UUCP (john z larese) writes: >I have just changed my place of work and I am now working in >a High security nuclear reactor. As employees, such as myself >enter the building, we pass all bags through a X-Ray detector >and walk through a metal detector. > >My question is, do any magnetic fields exist in either equipment >that might be high enough to damage Mag tapes? > In a time long ago ... NBS did a study and a report on the effects of magnetic fields on tapes. A short summary - locate the report for more: 1). Digital tapes are very difficult to erase. Audio tapes are easy as are video tapes. 2). Airport equipment will not normally erase a digital tape. 3). The old war story about a person walking into a computer room and erasing all the tapes or the one about the floor polished doing so is just that: a story, urban myths. 4). Their studies said that only a LARGE permanent magnet brought within 2 inches or the tape OR a special bulk eraser designed for digital tapes would erase it. BUT, it also cautioned about putting tapes near a disk drive with a large solenoid magnet or near the power supply of an X-ray machine. It also didn't address floppy disks. BTW it did discuss temperature and humidity, etc. as well. So check NTIS or NBS for the report. -- =Dennis L. Mumaugh Lisle, IL ...!{att,lll-crg}!cuuxb!dlm OR cuuxb!dlm@arpa.att.com
aad@stpstn.UUCP (Anthony A. Datri) (07/16/88)
In article <588@bnlux0.bnl.gov> larese@bnlux0.UUCP (john z larese) writes: >I have just changed my place of work and I am now working in >a High security nuclear reactor. I sure hope you've got some lead underwear:-) Those containment vessels can get a little warm:-) But seriously, my dad works for Babcock & Wilcox (or what's left of them -- thanks, ex-pres Jimmy), and I know what you mean. -- @disclaimer(Any concepts or opinions above are entirely mine, not those of my employer, my GIGI, or my 11/34) beak is beak is not Anthony A. Datri,SysAdmin,StepstoneCorporation,stpstn!aad
caasnsr@nmtsun.nmt.edu (Clifford Adams) (07/17/88)
In article <1925@cuuxb.ATT.COM> dlm@cuuxb.UUCP (Dennis L. Mumaugh) writes: >In a time long ago ... NBS did a study and a report on the >effects of magnetic fields on tapes. A short summary ... [summary on X-rays and Mag tapes deleted --caa] >... It [also] didn't address floppy disks. From experience... I was in California, and copied some floppy disks for my Commodore 64 computer. On a flight to Colorado Springs, the disks were run through the X-ray machine used for carry-on luggage. Most of the information survived. Less than 1 bit per 256 bytes was changed. Unfortunately, this destroyed almost all programs on the five disks. The disks for the Commodore 64 store 174K of information per side (348K/disk). Think of the damage to high-density formats that may store a megabyte or more per floppy disk. >=Dennis L. Mumaugh > Lisle, IL ...!{att,lll-crg}!cuuxb!dlm OR cuuxb!dlm@arpa.att.com -- Clifford A. Adams --- "I understand only inasmuch as I become." ForthLisp Project Programmer (Goal: LISP interpreter in Forth) caasnsr@nmtsun.nmt.edu ...cmcl2!lanl!unm-la!unmvax!nmtsun!caasnsr
danno@microsoft.UUCP (Daniel A. Norton) (07/18/88)
What I always do is carry any tapes and diskettes with me (rather than
keeping them with luggage) and hand them to the person at the security
check. They take a look at it and hand it back to me on the other
side, without passing it through any equipment. No hassles, no worry.
--
Any opinions expressed are mine, not my employer's.
nortond@microsof.beaver.washington.EDU nortond%microsof@uw-beaver.ARPA
{decvax,decwrl,sco,sun,trsvax,uunet,uw-beaver}!microsof!nortondsoley@ontenv.UUCP (Norman S. Soley) (07/20/88)
In article <1620@microsoft.UUCP>, danno@microsoft.UUCP (Daniel A Norton) writes: > What I always do is carry any tapes and diskettes with me (rather than > keeping them with luggage) and hand them to the person at the security > check. They take a look at it and hand it back to me on the other > side, without passing it through any equipment. No hassles, no worry. There is at least 1 US airport (Detroit I think) where you can't do this. Everything, film, tapes, disks, laptops, doesn't matter how sensitive goes throught the X-Ray machine. And the "nice" security man with the sidearm simply won't take any arguements. If you want to fly you put your stuff in the machine. There is a sign in all Canadian airports informing passengers that they have a right to decline an inspection but by doing so they also decline the priviledge of being allowed to board (that's not how it is worded but that's the jist of it). I travel a lot in Canada and I've yet to have a hand inspection refused but boy have I gotten some dirty looks! -- Norman Soley - Data Communications Analyst - Ontario Ministry of the Environment UUCP: utgpu!ontmoh!------------\ VOICE: +1 416 323 2623 {attcan,utzoo}!lsuc!ncrcan!ontenv!norm "witty saying not available due to writers strike"